Railway-truss



(No Model.)

O. SMITH.

. RAILWAY TRUSS. No. 430,304.

Patented June 17, 1890.

UNITED STATES PATENT OFFICE.

OLIVER C. SMITH, OF IPSWVICH, MASSACHUSETTS, ASSIGNOR TO THE ELECTRIC RAPID TRANSIT COMPANY, OF NEW HAMPSHIRE.

RAI LWAY-TRUSS.

SPECIFICATION forming part of Letters Patent No. 430,304, dated June 17, 1890. Application filed December 26, 1889. Serial No. 334,994. (No model.)

To @ZZ whom, t may concern:

Be it known that I, OLIVER C. SMITH, of Ipswich, in the county of Essex and State of Massachusetts, have invented a new and usefulImprovement in Railway-Trusses, of which the following is a specification.

This is a compound truss for railways, the nature of the same being fully described below, and illustrated in the accompanying Io drawings, in which- Figure l is a side elevation of a truss embodying my invention; and Fig. 2 is a transverse vertical section on line ac, Fig. 1.

A, A', and A represent, respectively, up-

I 5 per, middle, and lower longitudinal timbers or string-pieces, and a a track supported directly by the string-piece A. The lon gitudinal center ot' the truss is at the upright a.

B B are vstruts between the upper stringzo piece A and the central string-piece A', se-

cured at their upper ends to the timber A by the bolts C, and at their lower ends to the lower string-piece A by the bolts D, passing through the timber A.

E E are struts between the central stringpiece A and the lower string-piece A, secured at their lower ends to the string-piece A by the bolts H and at their upper ends to the upper string-piece A by the bolts I,

3o passing through the timber A. The upper and lower struts B E are parallel with each other, as are the upper and lower rods I D, and the struts on both sides of the center of the truss incline toward such center.

3 5 K K are uprights secured between the central and lower timbers A A near the lower ends of the struts B, and preferably at such a distance therefrom that a line drawn longitudinally through said struts would pass through the centers of the said uprights.

L L are nprights secured between the central and upper timbers A A near the upper ends of the struts E, and preferably at such a distance therefrom that aline drawn longitud-inally through said struts would pass through the centers of the said uprights. By means of this combination of three timbers and the struts and uprights, arranged as above described, the struts take the strain of compression and the uprights sustain the resist- 5o ance of the extension by a direct support near the end of each strut and transfer part of the crushing weightof the load to the central string-piece and from it to the lower.' string-piece. By this arrangement it will be 5 5 seen that the bolts that hold the extension strain do not extend from the top to the bottom of the truss, but only to opposite sides of the middle string-piece. The bolts therefore cannot form an electrical connection be- 5o tween the top and'bottom (wooden) stringpieces, and rails fastened to them can be thus easily insulated for carrying a current of electricity. Again, the bolts D I are not subjected to a strain from screwing up the nuts too tight-ly, and allvtheir strength' is utilized in holding the weight of the truss and its load.

In an elevated railway constructed with this truss the rails can be -used to conduct eleotricity to the car-motor and return the cur- 7o rent to the generator. A

Having thus fully described my invention, what I claim, and desire to secure by Letters Patent, is

The herein-described compound truss, consisting, essentially, of the upper, lower, and middle string-pieces A A A, the struts B between the upper and middle string-pieces, the struts E between the lower and middle string-pieces, the nprights K between the 8o lower and middle string-pieces, the uprights L between the upper and middle stringpieces, the lifting-bolts I between the upper and middle string-pieces, and the lifting-bolts D between the lower and middle string- 8 5 pieces, substantially as set forth.

OLIVER C. SMITH.

Vitnesses:

HENRY W. WILLIAMS, .I M. HAETNETT. 

